March 24, 2021 at 9:36 am

Aitor

Subscriber

Hello Anand,nAs you say, this is the typical converging-diverging nozzle problem. I suppose that the geometry and stagnation enthalpy are fixed, so that you have only one variable: inlet pressure. Euler equations with additional simplifications (steady and isentropic flow, negligible mass forces...) lead to an algebraic system of equations whose solutions are indeed tabulated, so that you have an starting point to validate your results. These tabulated values also give you the operating regime of the nozzle depending on the stagnation inlet pressure. nFor these type of flows, I would recommend you the following:n1) Obtain the mentioned tabulated (or obtained with a nonlinear equation solver) results and get the values of the inlet pressure for the different regimes (subsonic, supersonic with shock waves inside the nozzle, supersonic without shock waves, supersonic with shock waves outside the nozzle, supersonic with expansion and shock waves outside the nozzle).n2) Perform numerical simulations for these cases. Starting with the subsonic case, you can check if numerical results give the expected regime, as well as verify other quantities as throat and outlet velocity.nBe careful with the domain extension and mesh quality if shock waves and/or expansion waves are present. If you have any discrepancy in any of the simulations, you can post here your problem.